Study Surfaces Potential Cause of Alzheimer's
Immune cells could be 'going rogue'
By Kate Seamons,  Newser Staff
Posted Apr 16, 2015 12:03 PM CDT
   (AP Photo/Carrie Antlfinger)

(Newser) – It's the hopeful sort of line you want to see in a press release about an Alzheimer's disease study: Research out of Duke University "not only points to a new potential cause of Alzheimer's but also may eventually lead to a new treatment strategy." The findings, published yesterday in the Journal of Neuroscience, involve immune cells in the brain; normally, their job is to protect, but as the Guardian puts it, they may be "going rogue" and actually spurring the development of the disease. The experiments on lab mice showed that those immune cells, called microglia, began to "divide and change" in the disease's early stages. The cells released an enzyme that consumes the nutrient arginine, which CBS News' chief medical correspondent explains is key to "the health of neurons of nerve cells," particularly in parts of the brain tied to memory.

When researchers then used a cancer drug (one not previously tested on Alzheimer's) to block the enzyme release before the onset of symptoms in mice, they were able to prevent the disease's "characteristic brain plaques and memory loss," the release explains. Lead author Carol Colton says the findings "break the stalemate of ideas in Alzheimer's," and the Guardian explains why. Trials for Alzheimer's drugs have been a resounding failure (99.6% of them between 2002 and 2012), and those drugs have mainly attempted to do the same thing: chip away at the accumulation of sticky plaques. But new research suggests that by the time the plaques are there, it's already too late. The Guardian does present one caveat to the study, explaining that the lab mice used "are not a perfect parallel for what happens in human brains." (Another potential cause of memory loss: Sleep apnea and snoring.)